vertex_paint_actor

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description must disclose behavioral traits. It mentions that 'apply_to_all_vertices: Must be true for this initial implementation' and notes the 'save' option, but does not explain side effects on existing vertex colors, reversibility, or prerequisites like material support for vertex colors. It is adequate for a simple mutation but lacks depth on potential impacts.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is compact and front-loaded with the primary purpose, followed by a structured Args list and a concrete example. The KB reference is secondary. Every sentence contributes value, with no redundancy or filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a complex operation like vertex painting, the description provides the essential parameters, an example, and a KB pointer. It notes the initial implementation limitation (apply_to_all_vertices must be true) and the optional save behavior. Given that an output schema exists (though not shown here), the description does not need to explain return values. It lacks explicit prerequisites (e.g., material must support vertex colors) but is reasonably complete for a first version.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The schema has no parameter descriptions (coverage 0%), but the description's Args section provides one-line explanations for all six parameters: actor_name, component_name, color (RGBA), lod_index, apply_to_all_vertices, and save. It adds meaningful semantics beyond the schema titles, though it omits details like color value range (0-1 vs 0-255) and the meaning of lod_index. Still, it compensates well for the schema's lack of descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb and resource: 'Apply component override vertex colors to a placed StaticMeshActor/component.' This clearly distinguishes it from general actor manipulation tools like set_actor_property or set_static_mesh_properties, which do not target vertex painting. It is not a tautology and provides immediate clarity on what the tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description states the tool applies to 'a placed StaticMeshActor/component', giving context on when to use it (on placed actors, not asset definitions). It does not explicitly name alternatives or exclusions, but the parameter list and mention of 'component override vertex colors' implies it is for paint operations rather than general property setting. The KB link provides additional reference but is not inline guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.